Last year's carnival champion Vila Isabel closed out the first night of Rio's Samba parade as dawn broke Monday, with a glittering spectacle dedicated to the theme of metamorphosis that included dozens of dancers illustrating man's evolution from monkeys.

The group seemed an early favorite, with its 3,800 dancers and drummers marching through the Sambadromo stadium just as the sun began to rise, catching the gilt-encrusted costumes with its rays.

Another crowd pleaser was Mangueira, which paraded with 4,500 dancers and drummers behind an enormous pink and green fire-spitting float that recalled ancient Rome.

Estacio de Sa, Rio's oldest samba group, opened the parade Sunday night in a fusillade of fireworks with a troupe of Aztec-inspired dancers. That shimmering, golden float was crowned with a lion's head, its jaws in motion and a huge golden paw sweeping from side to side.

"It's loud, lots of pretty women. It's what every gringo wants," shouted 26-year-old Eric Scuderi, an electronics salesman from Maryland who joined 60,000 fans in the stadium, which was built exclusively for the parades.

Seven more groups will parade from Monday night into Tuesday morning, and judges will select the champion Wednesday afternoon.

The spectacle is more than a party; it is a hard fought competition.

Groups spend upward of a million dollars to mount 80-minute-long shows featuring hundreds of dancers, preening for a panel of judges made up of folklorists, musicologists and carnival scholars.

The 13 competing dance groups come from the city's shantytowns, and their showdown is a welcome distraction from the gunfights between drug traffickers, militias and police that have left at least 15 dead over the past week alone in the hills around downtown Rio. Adoring fans follow the live broadcasts with a passion reserved only for the World Cup.

This year's dispute is especially hot because the two schools with the lowest scores will drop to the second division, while the champion of the second division will move up. The idea is to reduce the number of schools from 14 to 12 and wrap up the parade at an earlier hour. In the past, the Samba parade dragged on well past dawn, ending as late as 9:30 a.m., with revelers often struggling under the weight of heavy costumes under the punishing tropical sun.

The schools are judged in 10 different categories including music, the quality of dancing and floats, parade theme and crowd reaction. A less than perfect score can dash a school's chances of victory.

Being relegated to the second division means less television exposure and the loss of lucrative sponsorships.

It has long been an open secret that funding for the parade comes from an illegal numbers game known here as the "jogo do bicho," Portuguese for animal game, but legitimate sponsors also have emerged in recent years, such as corporations and Brazilian states.

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